An effective method for evaluating highand low-temperature fatigue of structural elements

For geometrically complex designs of nuclear power plants, the justification of cyclic strength based on modern approaches is a time-consuming and resource-intensive process. From a practical point of view, the regulatory documents on the justification of the strength of nuclear power structures suggest the most simplified approach. The article numerically substantiates the inapplicability of such an approach for the case of non-isothermal cyclic loading. In this regard, a new effective methodology has been developed for assessing the fatigue of structures under isothermal or non-isothermal cyclic loads. Based on numerical elastic-plastic calculations of classical problems of deformation of cylindrical rods with deep annular incisions of various sharpness, the effectiveness of the developed technique has been confirmed.

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